title: The incidence of disorders of sexual differentiation and chromosomal abnormalities of cryptorchidism and hypospadias stratified by meatal location.
abstract: OBJECTIVE
  Routine karyotype analysis has been recommended for patients with cryptorchidism and hypospadias. However, it is unclear whether karyotyping should be obtained in all patients, or tailored to the severity or degree of hypospadias. Therefore, we analyzed the incidence of chromosomal abnormalities in patients with distal or proximal hypospadias and concomitant cryptorchidism.
  
  
  METHODS
  We reviewed the records of patients with cryptorchidism and hypospadias treated at a pediatric hospital between 1994 and 2006. Data collected included karyotype analysis, gonad palpability, and meatal and testes location at time of surgery. Patients with retractile testes and congenital adrenal hyperplasia were excluded from analysis.
  
  
  RESULTS
  We identified 44 patients with hypospadias and cryptorchidism (26 with proximal and 18 with distal hypospadias). Karyotype information was available in 25 patients (19 with proximal and 6 with distal hypospadias). None of the patients with distal hypospadias and cryptorchidism had an abnormality of a sex chromosome. In contrast, chromosomal abnormalities were present in 6 of 19 individuals (32%) with proximal hypospadias and cryptorchidism. The most common abnormality was mixed gonadal dysgenesis in 3 patients, followed by autosomal translocations in 2 and 48XY aneuploidy in 1.
  
  
  CONCLUSIONS
  When karyotype information was stratified by meatal location with cryptorchidism we found no significant chromosomal abnormalities in distal hypospadias and cryptorchidism, whereas a third of patients with proximal hypospadias and cryptorchidism had an abnormal karyotype. Karyotype analysis appears to be important in individuals with cryptorchidism and proximal hypospadias but of little benefit in patients with distal hypospadias and palpable undescended testes.
authors.affiliation: Division of Pediatric Urology, Washington University, St Louis Children's Hospital, St Louis, Missouri, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Cox
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Coplen
authors.forename: Paul F
authors.initials: PF
authors.lastname: Austin
mesh_terms: D002675:Child, Preschool; D002869:Chromosome Aberrations; D003456:Cryptorchidism / Q000150:complications / Q000453:epidemiology* / Q000235:genetics*; D012734:Disorders of Sex Development / Q000150:complications / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D007021:Hypospadias / Q000145:classification / Q000150:complications / Q000453:epidemiology* / Q000235:genetics*; D015994:Incidence; D007223:Infant; D008297:Male